The Mere Mile will see supporters of the Robert Jones and Agnes Hunt Orthopaedic Hospital's League of Friends attempt to swim a mile in Ellesmere's mere.
And while it will be just a "mere mile" for some of the elite swimmers, for others who only took to the water to get fit in lockdown it will be a massive achievement.
The event is being held on the afternoon of September 13, sponsored by Swimfinity, which gives swim coaching at the mere, and helped by other local businesses.
Anna Unsworth, fundraising co-ordinator for the hospital charity said that lockdown has seen all the league's income stream lost, whether its popular hospital cafe or the dozens of events hosted by the various branches of the league.
"I had always wanted to take up swimming and starting going to the sessions at the mere with Swimfinity," said Anna.
"I was talking to James and Nicky about the loss of fundraising events and we came up with this swim. At first I thought we might get 10 people to take part - we now have 100.
"They include recreational swimmers for whom the mile will be a huge challenge, and what I would call the elite swimmers, including some from the Titans at Ellesmere College and as far away as the Stourbridge swim club."
Others include members of the Trismart group which swims at the mere on Tuesday evenings and former patients and relatives of patients.
Anyone who wants to sponsor the swimmers can do so at https://www.justgiving.com/campaign/meremile.
Ruth Martin from Oswestry has reason to thank the hospital after her brother, Will, spend six months in its Midlands Centre for Spinal Injuries, following a road accident and initial surgery at Stoke.
"During the pandemic, I felt a bit useless. I'm not a key worker and the best thing I could do was to stay at home," he said.
"Now we are allowed back out in open spaces I'd really like to do something to support the amazing League of Friends at the RJAH Hospital and help it recoup some of the money lost over the last few months, whilst still supporting the staff and patients at the hospital.
"It’s turning out to be quite the challenge as a non-swimmer, but the support of the SwimFinity coaches and other fundraisers has been fantastic.
"It might take me a while to get around the mile long course, but I’ll be doing it."
Linda Arthan who lives in St Martins, travelled across Europe and as far as New Zealand as a GB Triathlete. Sporting injuries have seen her have three operations at the Orthopaedic Hospital.
"I love swimming and have swum in the mere on Tuesday evenings for many years," said Linda.
"I had elective surgery on my foot in February and had hoped swimming would be a big part of my physiotherapy. But then we had lockdown.
"Eventually I was able to get hold of a portable pool for the garden and attached myself to a bungee so I could swim without going anywhere."
As well as doing the Mere Mile herself, Linda will be taking to the water in a kayak as part of the safety and support team.